Fumes control system



Feb. 2, 1960 Original Filed Oct. 1, 1952 H. C. HAWLEY FUMES CONTROLSYSTEM 3 Sheets-Sheet 1- IN V EN TOR.

Feb. 2, 1960 H. c. HAWLEY 2, 23,2

FUMES CONTROL SYSTEM Original Filed Oct. 1, 1952 3 Sheets-Sheet 2 5a i5a IN VEN TOR. HARRY Cf 6642/5151;

ATY'OFNFK Feb. 2, 1960 H. c. HAWLEY FUMES CONTROL SYSTEM 3 Sheets-Sheet3- Original Filed Oct. 1. 1952 .r 4 I, u

IN VEN TOR. HA1??? 6 Aka/m, BY.

May/.1

I A? T 01?? K United St t s at .9

F UMES CONTROL SYSTEM Harry C. Hawley, Wabash, Ind.

Continuation of application Serial No. 312,543, October 1,1952. Thisapplication December 16, 1957, Serial No. 703,727

12 Claims. (Cl. 98115) The present specification constitutes acontinuation of my copending application, Serial Number 312,543, filedOctober 1, 1952 for a Fluid Handling Valving System which, in turn, is acontinuation-in-part of my earlier-filed application Serial Number240,729, filed August 7, 1951, for a Fluid Handling Valving System bothnow abandoned.

The present invention relates to a fumes control system which dependslargely for its success upon a fluid handling valving means, and theinvention is primarily concerned with the provision of means wherebycommunication will be effectively established and maintained between tworelatively movable chambers, whlle communication with the atmosphere isprevented, regardless of the relative positions of the chambers. Inaddition to this primary object, it is a further object of the inventionto provide means whereby communication may be always maintained betweena source of vacuum and an element having a wide range of movementrelative to said source. A further object of the invention is to providenovel means, associated with a movable chamber, for establishing andmaintaining communication between the chamber and an elongated,stationary header, regardless of the position of said chamber in itspath of movement longitudinally of said header.

A still further object of the invention is to provide a system wherebyfumes arising from any source, as, for

instance, from a pool of molten metal in a pot or ladle which must, inordinary usage, be transported from point to point, will be capturedsubstantially at their point of origin and scavenged for discharge at apoint Where their noxious character will be rendered innocuous.

Further objects of the invention will appear as the descriptionproceeds.

To the accomplishment of the above and related objects, my invention maybe embod ed in the forms illustrated in the accompanying drawings,attention being called to the fact, however, that the drawings areillustrative only, and that change may be made in the specificconstructions illustrated and described, so long as the scope of theappended claims is not violated.

Fig. 1 is a more or less diagrammatic view of an installation embodyingmy invention, the header and the movable chamber being shown intransverse section; 'Fig. 2 is a longitudinal section of the header andthe chamber or carriage of Fig. 1, taken substantially on the Fig. 8 isa transverse section taken substantially on the line 8--8 of Fig. 6.

The valving means herein disclosed finds primary utility in thescavenging of fumes from a pouring ladle in a foundry, and it has beenillustrated, and will be described, in that environment. It will beclear, however,

that such means will find substantial utility in other en-.

, in which the system is housed. Conventionally, fumes which rise fromthe ladle are allowed to emerge freely into the building, thuscontaminating the atmosphere to an extent which is always disagreeable,and in some instances may actually be dangerous to the health of theworkers concerned with the operations.

It is desirable, therefore, to provide a hood or canopy 16 over theladle to receive such fumes, and to provide means for conducting thosefumesto a point of discharge so arranged as to obviate thosedisadvantages. The canopy must, however, move with the ladle whereverthe latter goes, if the system is to be effective, and the travel pathof such ladle is conventionally so extensive as to malte the use offlexible conduit means, connecting the canopy with an exhaust fan or thelike, entirely impractical.

According to my invention, therefore, I provide conduit means, which maybe rigid, connecting an exhaust fan with the interior of an elongatedheader paralleling the trackway 14 throughout its length; and then 1provide a movable, chamber-forming carriage, supported upon a secondtrackway following the first, connect that carriage chamber with thecanopy through short conduit means which may' be rigid, though it ispreferably flexible at least to a sliglit degree, and then provide meanswhereby the interior of the carnage chamber is maintained always in opencommunication with the interior of the header, while both the header andthe chamber are always closed to the atmosphere except through the openmouth of the canopy.

As shown, then, the canopy 16 is supported from the carriage 12 througha conduit 17 from which conduit means 18 (shown as a flexible tube)leads to the chamber 19 formed in a carriage 20. Suitable supports 21carry a stationary header 22 wh.ch parallels the course of the trackway14 which, in the form of invention illustrated in Figs. 1 and 2, issubstantially rectilinear. The header 22 is completely closed, exceptfor one or more outlet conduits 24, leading to one or more. exhaustfans, and

except for the fact that its top wall 25 is formed with a slot 26extending substantially from end to end of the header.

A web or strip 27, which may be formed of any flexible materialsubstantially impervious to fluid flow therethrough, is arranged to spanthe slot 26 and tooverlap the lateral edges thereof on the outersurfaceof the wall 25. One end of said web is anchored as at 28 beyondthe adjacent end of the slot 26, while the other end of said web extendsbeyond the opposite end of the slot, so that the web, when in contactwith the wall 25, is capable of sealing the slot 26 completely.Preferably, a resilient, longitudinal tension is applied to said web toassist in maintaining proper sealing engagement between the web and thewall 25. In the illustrated embodiment of the invention, the anchormeans 28 fixes the first-mentioned end of the web, while the oppositeend 29 of the web runs past the opposite end of the slot 26, over aroller means 30, and, depending therefrom, supports a weight 31 whichapplies a resilient longitudinal tension to the entire length of theweb. Alternatively, spring means might be attached to one orboth ends ofthe web; or the web might be formed of material such as rubber having asubstantial inherent resiliency, in which case both ends of the webmight be fixedly anchored.

The carriage is supported by wheels 32 arranged to run upon trackelements which, in the illustrated form of the invention, are rails 33carried by the header 22. The chamber 19 of the carriage 20 is closedexcept for its communication with the conduit 18, and except that itsbottom is open to the wall of the header 22, and envelops alongitudinally short section of the web 27.

Thusjthe chamber 19 always registers with a short section of the slot26, as the carriage 20 moves longitudinally of the header 22.Preferably, means such as one or more fingers 34 will provide a drivingconnection between the carriage 12 and the carriage 20 whereby thelatter will follow themovements of the 'former.

Within the chamber 19, the carriage 20 supports a transverse member uponan axis removed a substantial distance from the plane of the wall 25;and the web 27 is led over and supported upon that surface of saidtransverse member remote from said wall 25, whereby the supportedsection of said web is held out of sealing relation withthe slot 26.Other transversemembers, spaced oppositely from said first-named memberin the direction of length of the header, press upon the outer surfaceof the web ahead of, and behind, the first-named member to hold saidweb, at opposite ends of such supported section, in sealing relationwith said slot. In the illustrated embodiment of the invention, andpreferably, each of these three transverse members will be a roller.

Thus, a roller 35 is journal mounted inside the carriage upon trunnionmeans 36 suitably supported within the chamber 19, said roller spanningthe width of the slot 26, and engaging the inner face of the web 27 tohold a section of said web, as shown in Fig. 2, out of sealing relationwith the slot 26, the axis of rotation of said roller beingsubstantially parallel with the header Wall 25 and transverse to thedirection of length of the header 22. Ahead of the roller 35, a secondroller 38, supported upon trunnion means 39, is mounted in the chamber19 to span the width of the slot 26. As shown, the trunnion means 39will be guided for vertical movement in retaining slots 40 suitablyprovided at opposite sides of the chamber 19, the axis of rotation ofthe roller 38 being substantially parallel with the axis of rotation ofthe roller 35. In the illustrated embodiment of the invention, gravitywill cause the roller 38 to hold that portion of the web 27 engaged bysaid roller in close contact with the wall 25 and in sealing relationwith the slot 26. A similar roller 41, having trunnion means 42 guidedin similar slots 43 is arranged behind the roller 35 for a similarpurpose.

It will be seen that the chamber 19 is closed to the atmosphere, but isalways open to the interior of the header 22 through that section of theslot 26, within the confines of the chamber 19, which is held open bythe engagement of the roller 35 with .the enveloped section of the web27. Preferably, strips of felt or the like, 44 and 45, willbe carried atthe lateral edges of the carriage 20 to bear on the wall 25, and similarstrips 46 and 47 may be carried at the forward and rearward edges of thecarirage, whereby leakage of air'into the chamber 19 is minimized. Thesesealing strips may be secured in place in any suitable fashion as, forinstance, by means of a ring 44 fastened within .the carriage by rivetsand clamping the strips against the adjacent carriage walls. a

As the carriage 20 moves along the trackway 33 in unison with movementof thecarriage'12 along the trackv.4 way 14 that section of the web 27currently within the chamber 19 will be lifted, by the roller 35, out ofsealing relation with the slot 26; while the rollers 38 and 41 will actto limit the longitudinal extent of the lifted section of the web.

If desired, the gravitational effect upon the rollers 38 and 41 may besupplemented by springs acting downwardly on said rollers. It will berecognized, of course, that the pressure dilferential resulting from theevacuation of the header 22 will eifectively hold the web 27 in sealingrelation with those portions of the slot 26 currently outside theconfines of the chamber 19, and that the longitudinal tensile stress towhich the web is subjected tends to prevent rumpling of said web as thecarriage 20 moves therealong.

The structure thus far described is eminently satisfactory in use in asystem in which the trackway 14, and hence the header 22, can berectilinear. In some installations, however, the equivalent of thetrackway 14 must be curved or sinuous, and in Figs. 3 and-4 I haveillustrated a somewhat more complicated embodiment of my inventionadapted for use in such installations.

Thus, where the header 50 must embody one or more curves, the slot 51may be formed in that header wall 52 which is substantially parallelwith the axis or axes of curvature of said header, and the trackway forthe chamber-forming carriage will comprise two rails 53 and 54 arrangedin a common plane at opposite edges of said wall 52. 'In this form ofthe invention, means must be provided for retaining the slot-sealing web57 against lateral movement relative to the slot, and I prefer toprovide boundary flanges 55 and 56 on the rails 53 and 54 to performthat function, as clearly shown in Fig. 3.

A carriage 58 is formed to provide a chamber 59 analogous to the chamber19; and saidcarriage is supported from the trackway in a novel mannernow to be described.

A hanger 60 rigid'with the carriage 58 provides a hearing 62 for thestem 63-of a bracket 64, whereby said bracket is oscillable, relative tothe carriage, about the axis of said stem which lies in, or parallel to,the common plane of the track rails 53 and 54. An axle 65 traverses thebracket 64 upon an axis perpendicular to the stem axis, and mounts agrooved wheel 66 supported upon the rail 53. The bracket 64 furthersupports two Wheels 67 and 68 upon axes parallel with the stern axis andequally and oppositely spaced from said common plane, said last-namedwheels engaging opposite surfaces of said rail 53.

Registering with the hanger 60 but secured to the opposite side of thecarriage is a second hanger 61 providing a bearing 69 for the stem 70 ofa second bracket 71. Said bracket 71 may be identical with the bracket64 but preferably will take the simplified form illustrated, having noequivalent of the wheel 66 and carrying only wheels 72 and 73 equivalentto'the wheels 67 and 68 and cooperating with the rail 54 in a similarmanner. Preferably, a rigid strap 74 will provide a mechanicalconnection between the bracket 64 and the bracket 71. Of course, asimilar set of brackets and associated parts will be arranged at eachend of the carriage 58.

Within the chamber 59 is arranged a roller 75 carried on trunnion means76 supported in fixed bearings. Said roller is functionally equivalentin all respects to the roller 35 and acts upon the web 57 as the roller35 acts on the web 27.

A roller 77 is carried on trunnion means 78 and is located ahead of theroller 75; while a similar roller 79 is carried on trunnion means 80behind the roller 75. In this form of the invention, the trunnion means78 is supported at the free end of a lever 81 swung from a pivot rod 82traversing the chamber 59, and a coiled spring 83 is confined between afixed abutment 84 in the carriage 58 anda seat 85 on the lever 81 topress the roller 77 resiliently toward the header wall 52. Similarly,

'the trunnion means 80 is supported at the free end'of a lever 86 swungfrom a pivot rod 87 traversing the chamber 59, and a coiled spring 88acts on the lever 86 to press the roller 79 resiliently toward theheader wall 52.

The action of this form of the invention is broadly equivalent to thatof the form illustrated in Figs. 1 and 2, except that the carriage 58 isable readily to follow curves in the wall 52 and the rails 53 and 54.The wheels 66, of course, support the carriage and tend to follow thecurvature of the rail 53, while the wheel-supporting brackets turn aboutthe axes of their stems 63 and 70 and the wheels 67 and 68 and thewheels 72 and 73 hold the carriage against lateral movement relative tosaid rails.

As said before, the last described embodiment of my invention issomewhat more complicated than the embodiment first described. While itsuse fulfills a need not satisfiable by the first embodiment, it, too, issomewhat limited in its application. For these reasons, I haveillustrated and shall now describe, a further modification of myinvention somewhat simplified and more universal in its application.

Referring now to Figs. 5 to 8 inclusive, the header 90, having a numberof curved portions 91 therein, has the slot 92 formed in the upper wall93 thereof. The slotsealing web 94 is shaped to conform to the contourof header 90 and is held against lateral displacement by the provisionof longitudinally-extending guide flanges 95 and 96 upstanding from wall93 and skirting the opposite rims of slot 92 as most clearly shown inFigs. 5 and 8. Flanges 95 and 96 are supported on the inner edges ofhorizontal plates 97 and 98 securely fixed to the upper wall 93 andextending laterally beyond the sides of the header 90, for a purposelater to become apparent.

The carriage 99 is formed to provide a chamber 100 analogous to thechambers 19 and 59; and said carriage is supported on the header in amanner now to be described.

Within chamber 100, cross-headers 101 and 102 are supported on carriage99 near the opposite ends of said chamber. Each cross-header supports adepending spud 103 having a bore 104 therein along an axis substantiallyperpendicular to wall 93 and lying substantially in the median plane ofsaid carriage.

Journalled in each bore 104 is a king-pin 105 supporting a hub 106having an axial bore 107 therethrough substantially normal to bore 104.A trunnion 103 is mounted in each bore 107 and has journalled on theends thereof a pair of rollers 109 and .110. The spacing between theopposite ends of said rollers is substantially the distance between theinner surfaces of guide-flanges 95 and 96. The rollers at each end ofthe carriage are each disposed between the flanges 95 and 96 and as suchact as wheels whereby carriage 99 is supported on header 90.Additionally, since the rollers 109 and 110 run on the outer surface ofthe web 94, they act to hold said web in sealing contact with headerWall 93.

For the purpose of holding that portion 111 of web 94 currently inregistry with chamber 100, out of sealing engagement with slot 92, Iprovide a shaft 112 supported within chamber 100 upon suitable bracketscarried by carriage 99, said shaft being spaced substantially from tothe longitudinal length of header 90. Rollers 117 are so positioned ondolly 114 as to be laterally engaged by the inwardly facing surfaces ofguide flanges 95 and 96.

carriage 99 enters a curved portiQn 91 of the header 90,'the'mid-portion of the carriage will be shifted laterally relative tothe header, its slot 92 and the web 94. Due to the coaction betweenwheels 117 and flange 96, the dolly 114, however, is compensatinglylaterally shifted on shaft 112 to retain roller 113 axially in propercooperative association with the web portion 111. Upon movement ofcarriage 99 from curved portion 91 to a straight portion of header 90,flange engages rollers 117 and again shifts roller 113 relative to thecarriage so as to maintain it always in proper position relative to webportion 111.

Suitable gasket means 118 provides a substantially tight seal betweenthe carriage skirt and the horizontal plates 97 and 98.

It will, of course, be apparent that a series of apertures,longitudinally spaced apart a distance less than the length of chambers19, 59 and might be formed in the headers 22, 40 or 90, in place ofcontinuous slots 26, 51 or 92, and it is intended that such anarrangement shall be included in the expression alongitudinally-extending slot, or the like.

I claim as my invention:

1. In a fume-controlling system, a hood adapted to be mounted inoverlying relation to the open mouth of a container for a fuming liquid,an elongated header having one wall thereof formed to provide alongitudinally-extending slot, fluid-evacuating means connected to theinterior of said header, a flexible, substantially fluid-imperviousstrip disposed exteriorly of said one header wall and overlying andnormally closing said slot, a carriage, trackway means supporting saidcarriage for longitudinal movement relative to said header, saidcarriage having walls extending away from said strip, said walls beingjoined by a common outer wall, the edges ofsaid first-named carriagewalls adjacent said strip being provided with sealing means extendingalong said wall edges and engaging said one wall of said header todefine a chamber closed to the atmosphere, said chamber registering witha longitudinally-short section of said slot and enveloping therein acorresponding section of said strip, strip-supporting means, meanscarried by said carriage and mounting said strip-supporting means withinsaid chamber upon an axis substantially spaced from said one header walland extending transversely relative to the length of said header, saidstrip-supporting means engaging that surface of said correspondingsection of said strip which faces said one header wall to support theengaged section of said strip in spaced relation to said slot,strip-engaging means, means carried by said carriage and mounting saidstrip-engaging means within said chamber upon axes ahead of and behindsaid stripsupporting means and extending transversely relative to thelength of said header, said strip-engaging means bearing against theopposite surface of said strip to press the same into intimate contact,within said chamber, with said one header wall in sealing relation withsaid slot, conduit means connecting the interior of said chamber withthe interior of said hood, and means enforcing movement of said carriagelongitudinally of said header to follow movement of said hood with saidcontainer.

2. A fume controlling system for a brass foundry or the like including amobile ladle for transporting fuming moltenmetal from a furnace to aplurality of spaced molds, a hood, means for connecting said hood inoverlying relation to the open mouth of such a ladle, an elongatedheader having one wall thereof formed to provide alongitudinally-extending slot, fluid-evacuating means connected to theinterior of said header, a flexible,

substantially fluid-impervious strip disposed exteriorly of said oneheader wall and overlying and normally closing said slot, a carriage,trackway means supporting said carriage for longitudinal movementrelative to said header, said carriage having walls extending away fromsaid strip, said walls being joined by a common outer wall, the edges ofsaid first-named carriage walls adjaenemas? cent said strip:beingprovided with-.sealingineans extending along said wall edges andengaging said one wall of said header to definea chamber. closed to theatmos phere, said chamber registering with a longitudinallyshort sectionof said slot and enveloping therein a corresponding section of saidstrip, strip-supporting means, means carried by said carriage andmounting said stripsupporting means within said chamber upon an axissubstantially spaced from said .one header wall and extendingtransversely relative to the length of said header,

said strip-supporting means engaging that surface of said correspondingsection of said strip which faces said one header wall to support theengaged section of said strip in spaced relation to said slot,strip-engaging means, means carried by said carriage and supporting saidstrip-engaging means within said chamber upon axes ahead of and behindsaid strip-supporting means and extending transversely relative to thelength of said header, said strip-engaging means bearing against theopposite surface of said strip to press the same into intimate contact,within said chamber, with said one header wall in sealing relation withsaid slot, said strip engaging means being located immediately adjacenttwo of said carriage walls, conduit means connecting the interior ofsaid'chamber with the interior of said hood, and means "enforcingmovement of said carriage longitudinally 'of said header to followmovement of saidhood with said ladle.

3.1n a system of the class described, an elongated header provided withlongitudinally-extending slot means opening through one wall thereof,means for continuously evacuating said header, trackway means supportedfrom and following the length of said header, a carriage supported andguided upon said trackway means for longitudinal travel relative to saidheader, said carriage having'walls extending away from said header, saidwalls being joined by a common outer wall and defining an open sideopposite said common wall presented to said one header wall, saidcarriage thus being formed to define, with said header wall, a chamberclosed to the atmosphere, gasket means carried by said carriage wallsand engaging said header wall to provide a fluid seal for said chamber,a flexible, substantially fluid-impervious strip exteriorly arrangedupon said one header wall to span said slot means, having alongitudinally-short sec- 7 tion enveloped Within said chamber andhaving a fluidsealing relation with said slot means from end to endthereof except within said chamber, strip-supporting means, meanscarried by said carriage and mounting said strip-supporting means whollywithin said chamber upon an axis transverse with respect to the lengthof said header and significantly spaced from said header wall, saidstrip-supporting means engaging that surface of the strip sectioncurrently enveloped within said chamber which surface-faces said headerwall to hold a portion of such enveloped section out of sealing relationwith said slot means, two strip-engaging means, means carried by saidcarriage and mounting said respective strip-engaging means wholly withinsaid chamber upon axes substantially parallel with, and oppositelyspaced in the direction of header length from, the axis of saidstrip-supporting means, each of said strip-engaging means bearing uponthe opposite surface of said strip section within said chamber, to presssaid strip into engagement means supporting said carriage on said upperwall for longitudinal mo'vement relative to saidheader, said carriagehaving walls with sealing means extending along the lower edges of saidwalls engaging said upper wall of said header to define a chamberregistering with a longitudinally-short section of said slot andreceiving therein the corresponding section of said web, duct meansconnecting said chamber with a source of fluid, a Web-supporting roller,means supporting said web-supporting roller on said carriage within saidchamber upon an axis substantially spaced from said one header wall andextending transversely relative to the length of said header, saidweb-supporting roller engaging a lower surface of said correspondingsection of said web to support the engaged section of said Web in spacedrelation to said slot, web-engaging rollers, means supporting saidweb-engaging rollers on said carriage within said chamber, saidweb-engaging'rollers being located respectively behind and ahead of saidweb-supporting roller and engaging the upper surface of said web topress the same into intimate contact with said one header wall insealing relation with said slot, said web-engaging rollers being locatedimmediately adjacent two of said carriage walls, said carriage beinginternally formed to providea plurality of slots elongated in adirection substantially normal to said one header wall, and each of saidmeans supporting said web-engaging rollers comprising a trunnion havingits ends mounted in a mating pair ofsaid slots.

5. In a device of the class described, an elongated header having onewall thereof formed to provide a longitudinally-extending slot, ductmeans connecting said header with fluid-evacuating means, web means,means supporting said web means on the exterior of said one header wallwith said web means overlying and normally closing said slot, acarriage, means supporting said carriage for longitudinal movementrelative to said header, said carriage being formed to define a chamberregistering with a longitudinally-short section of said slot andreceiving therein the corresponding section of said web means, ductmeans connecting said chamber with a source of fluid, web-supportingmeans, means supporting said web-supporting means on said carriagewithin said chamber upon an axis substantially spaced from said oneheader wall and extending transversely relative to the length of saidheader, said web-supporting means engaging that surface of saidcorresponding section of said web means adjacent said one header wall tosupport the engaged section of said web means in spaced relation to'said slot, web-engaging means, means supporting said web-engaging meanson said carriage within said chamber, said web-engaging means beinglocated respectively behind and ahead of said web-supporting means andengaging the opposite surface of said web means to press the same intointimate contact with said one header wall in sealing relation with saidslot, each of said means supporting said web-engaging means being atrunnion, said device further including a lever supporting eachtrunnion, and pivot means for each lever supported on said carriage,each pivot means supporting its lever adjacent one end to swing in aplane substantially perpendicular'to said one header wall.

6. The device of claim 5 including spring means:acting on said leversand resiliently urging the free ends of said levers toward said oneheader'wall.

7. In a device of the class described, an elongated header having onewall thereof formed to provide a longitudinally-extending slot, ductmeans connecting said header with fluid-evacuating means, web means,means supporting said web means on the exterior of said one header wallwith said web means overlying and normally closing said slot, acarriage, means supporting said carriage for longitudinal movementrelative to said header, said carriage being formed to define a chamberregistering with a longitudinally-short section of said slot andreceiving therein the corresponding section of said web means, d'uctmeans connecting said chamber with a source of fluid, web-supportingmeans, means supporting said web-supporting means on said carriagewithin said chamber upon an axis substantially spaced from said oneheader wall and extending transversely relative to the length of saidheader, said web-supporting means engaging that surface of saidcorresponding section of said web means adjacent said one header wall tosupport the engaged section of said web means in spaced relation to saidslot, web-engaging means, means supporting said web-engaging means onsaid carriage within said chamber, said web-engaging means being locatedrespectively behind and ahead of said web-supporting means and engagingthe opposite surface of said web means to press the same into intimatecontact with said one header wall in sealing relation with said slot,said web-engaging means being rollers supported upon axes spacedlongitudinally relative to said header wall, and extending transverselyrelative to the length of said header, and spring means resilientlyurging said rollers toward said one header wall.

' 8. In a system of the class described, a trackway, a

- ladle for fuming molten metal supported from said trackway fortransportation therealong, a hood, means for connecting said hood inoverlying relation to the open mouth of said ladle for travel with saidladle, an elongated header paralleling said trackway, said headerbeingprovided with longitudinally-extending slot means in one Wallthereof, a carriage trackway means supporting said carriage forlongitudinal movement along said header, said carriage having wallsextending away from said one header wall, said walls being joined by acommon outer wall to define, with said one header wall, a chamberenveloping a longitudinally-short section of said slot means, gasketmeans extending along the edges of said carriage walls adjacent said oneheader wall and cooperating with said header to seal said chamberagainst fluid flow thereinto from the circumambient atmosphere, aflexible, substantially fluid-impervious strip exteriorly disposedagainst said one header wall and spanning said slot means in sealingrelation thereto except within said chamber, strip-supporting means,means in said carriage and mounting said strip-supporting means whollywithin said chamber, said strip-supporting means supporting a portion ofthe chamber-enveloped section of said strip out of sealing associationwith the chamber-enveloped section of said slot means, strip-engagingmeans, means in said carriage and supporting said strip-engaging meanswholly within said chamber, said strip-engaging means bearing upon thechamber-enveloped section of said strip, at separate points oppositelylongitudinally spaced from said strip-supporting means to press saidstrip into slotsealing engagement with said one header wall, conduitmeans connecting said hood with the interior of said chamber, and meansfor continuously evacuating said header, said chamber being constrainedto follow the travel of said ladle along said trackway.

9. In a device of the class described, an elongated header having onewall thereof formed to provide a longitudinally-extending slot, a pairof guide flanges upstanding from said one header wall substantiallyparallel with the lips of said slot and spaced oppositely outwardtherefrom, duct means connecting said header with fluidevacuating means,web means, means supporting said web means on the exterior of said oneheader wall with said web means overlying and normally closing saidslot, a carriage, means supporting said carriage for longitudinalmovement relative to said header, said carriage being formed to define achamber registering with a longitudinally-short section of said slot andreceiving therein the corresponding section of said web means, ductmeans connecting said chamber with a source of fluid, websupportingmeans, a shaft supporting said web-supporting means on said carriagewithin said chamber upon an substantially spaced from said one headerwall and p "extending transversely relative to the length cf said head-'er, said web-supporting means engaging that surface of saidcorresponding section of said web means adjacent said one header wall tosupport the engaged section of said web means in spaced relation to saidslot, web-engaging means, and means supporting said web-engaging meanson said carriage within said chamber, said webengaging means beinglocated respectively behind and ahead of said web-supporting means andengaging the opposite surface of said web means to press the same intointimate contact with said one header wall in sealing relation with saidslot, and said web means and said web-engaging means having transversedimensions substantially equal to the spacing between said guide flangesand engaging said one header wall between said guide flanges, saidweb-supporting means comprising an axially shiftable roller journalledupon said shaft for rotation about the axis thereof, said'device furthercomprising a dolly including frame means supported from said shaft atopposite ends of said roller and shiftable axially upon said shaft, andguide means supported from said frame means and engaging the innersurface of said guide flanges, said dolly having cooperative engagementwith said roller and being axially shiftable by said guide means to soshift said roller in conformity with. lateral deviations of said guideflanges.

10. In a device of the class described, an elongated header having onewall thereof formed to provide a longitudinally-extending slot, a pairof guide flanges upstanding from said one header wall substantiallyparallel with the lips of said slot and spaced oppositely outwardtherefrom, duct means connecting said header with fluidevacuating means,web means, means supporting said web means on the exterior of said oneheader wall with said web means overlying and normally closing saidslot, a carriage, means supporting said carriage for longitudinalmovement relative to said header, said carriage being formed to define achamber registering with a longitudinally-short section of said slot andreceiving therein the corresponding section of said web means, ductmeans connecting said chamber with a source of fluid, web-supportingmeans, means supporting said Web-sup porting means on said carriagewithin said chamber upon and axis substantially spaced from said headerwall and extending transversely relative to the length of said header,said web-supporting means engaging that surface of said correspondingsection of said web means adjacent said one header wall to support theengaged section of said web means in spaced relation to said slot,web-engaging means, and means supporting said web-engaging means on saidcarriage within said chamber, said webengaging means being locatedrespectively behind and ahead of said web-supporting means and engagingthe opposite surface of said web means to press the same into intimatecontact with said one header wall in sealing relation with said slot,and said web means and said webengaging means having transversedimensions substantially equal to the spacing between said guide flangesand engaging said one header wall between said guide flanges, each ofsaid means supporting said web-engaging means comprising a trunnion,king-pin means oscillably supported on said carriage upon spaced axessubstantially normal to said one header wall and each supporting one ofsaid trunnions in a plane substantially parallel to said one headerwall, said web-engaging means each comprising rollers journalled uponsaid trunnions and axially confined between said guide flanges.

11. In combination, an elongated header, means for contiuouslyevacuating said header, said header being provided with an elongatedslot opening through a wall thereof, a flexible web overlying said slotexternally of said header and normally sealing said slot against fluidmovement therethrough, a carriage, track means extending longitudinallyof, and supported from, said header and supporting said carriage forlongitudinal movement spasm? ill .relative :to said header, saidcarriage having walls I extending-away from said web, said walls beingjoined by a common outer wall, the edges 'of said :first-named carriagewalls adjacentsaid -web being provided with sealing means extendingalong said wall edges and-engaging saidone wall of'said header to definea chamber enveloping -a longitudinally-short section of saidWeb,web-supporting means within said chamber engaging the envelope'dwebsection to holdthesame spaced from said header Wall,- means 'insaidcarriage mounting said websupportingmeans, web-engaging means-withinsaid chamber engaging the enveloped web 'section at separate pointslongitudinally oppositely spaced ,from said websupporting means toipresssaid web firmlyagainst said header wall, means in said carriage mountingsaid webengaging means,- a hood, conduitmeans connecting said hood withthe interior of said chamber, -a mobile vessel .for'fuming-liquid, andmeans for connecting said hood against fluid movement therethrough, acarriage, track means extending longitudinally .of said header and sup-,porting said carriage for longitudinal movement relative to saidheader, said track means including opposite rails lying substantially ina'common plane at opposite edges of said slotted wall, a bracket on saidcarriage mounted for oscillation relative to said carriage about an axislying substantially in said common plane, a wheel journalled in saidbracket on an axis substantially perpendicular to said axis ofoscillation, said wheel running on one of said rails to support saidcarriage therefrom, a pair of wheels journalled in said bracket on axessubstantially parallel with said common plane to engage opposed surfacesof said one rail, said carriage defining a chamber enveloping a shortsection of said web, means within said chamber engaging the envelopedweb section to hold the same spaced from said header wall, and means forcontinuously evacuatingsaid header.

References Cited in the file of this patent UNITED STATES PATENTS2,495,376 Lusk Jan. 24, 1950 2,496,209 Homing Jan. 31, 1950 2,693,749Houdek Nov. 9, 1954 2,810,336 Sheifer Oct. 22, 1957 FOREIGN PATENTS19,838 Great Britain Oct. 2, 1905 462,135 Germany July 5, 1928 UNITEDSTATES PATENT IEFICE CERTIFICATE OF CORRICTION Patent No. 2923,22?February 2, 1960 Herry C. Hawley It is hereby certifiefl that errorippears in the printed Specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1O line 44, claim l0 for "and axis" read an axis same line, after"said" insert one -g line 69 claim 11, for "contiuous 13'! readcontinuously Signed and sealed this 5th day of Tuly 1960.

I'YCS'EAL) KARL H, AXLINE ROBERT C. WATSON Attesting Officer Comissionerof Patents

